Vertically adjustable demountable chair seat



June 23, 1959 V R. G. STALLARD 2,891,599

VERTICALLY ADJUSTABLE DEMOUNTABLE CHAIR SEAT Filed May 20, 1957- INVENTOR jaa ialla rd ATTORNEYS VERTICALLY ADJUSTABLE DEMOUNTABEE CHAIR SEAT Ross G. Stall'ard, Vallejo, Calif.

Application May 20, 1957, Serial No. 660,398

1 Claim. (Cl. 155-82) The present invention relates to vertically adjustable demountable chair seats, and is an improvement on my copending applications, Serial No. 577,785, filed April 12, 1956, now Patent No. 2,843,182, issued July 15, 1958, entitled Adjustable Chair Seat; and Serial No. 594,774, filed June 29, 1956, now Patent No. 2,854,063, issued September 30, 1958, entitled Adjustable Seat for a Chair.

The primary object of the invention is to provide an adjustable seat for a chair which can be fitted to chairs of varying widths and can be attached and detached without disassembling the chair.

Another object of the invention is to provide an adjustable chair seat which can be attached to a tubular chair back structure in which the tubular members are out of parallelism.

A further object of the invention is to provide an adjustable chair seat having the seat held in adjusted position by a simple cam lock.

A further object of the invention is to provide an ad justable chair seat which can be vertically adjusted as well as adjusted for width without the use of tools of any kind.

A still further object of the invention is to provide an adjustable seat for chairs which is inexpensive to manufacture, easy to use, and durable in service.

Other objects and advantages will become apparent in the following specification when considered in the light of the attached drawings, in which:

Figure 1 is a perspective view of the invention.

Figure 2 is an enlarged fragmentary side elevation of the invention illustrating in particular the cam lock structure in locked position.

Figure 3 is a view similar to Figure 2 illustrating the cam lock structure in unlocked position.

Figure 4 is an enlarged fragmentary horizontal crosssection taken along the line 4-4 of Figure 1, looking in the direction of the arrows.

Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures, the reference numeral indicates generally a chair constructed in accordance with the invention.

The chair 10 is formed of tubular material and includes a pair of front legs 11 and 12, a pair of horizontal members 13 and 14 integrally formed with the upper end of the legs 11 and 12, respectively, and extending rearwardly therefrom.

A cross member 15 extends between the horizontal members 13 and 14 at the forward edge thereof adjacent the upper ends of the legs 11 and 12. A pair of rear legs 16 and 17 are secured to the rear ends of the horizontal members 13 and 14 and a cross member 18 extends between the rear ends of the horizontal members 13 and 14 adjacent the upper ends of the rear legs 16 and 17.

The rear legs 16 and 17 are secured to the horizontal atent O I 2,891,599 Patented J une' 23,- 1959 members 13 and 14 by welding or the like. U-shaped back member 19' extends integrally upwardly from the horizontal side members 13 and 14 and includes generally upright'tubular sidemembers' 20"a'n'd"21. The chair 10' comprises generally an open tubular framework secured together in a conventional welding manner.

A generally rectangular seat 22 is arranged in horizontal relation above the legs 11, 12, 16 and 17 and forwardly of the back member 19, as is best seen in Figure 1. The seat 22 is supported on a U-shaped tubular seat frame 23 which is arranged in horizontal relation and has the free ends 24 and 25, respectively, thereof extending rearwardly.

The free end 24 of the seat frame 23 is upwardly offset and has a tubular cam 26 secured to the terminal end thereof. The axis of the tubular cam 26 extends generally perpendicularly to the U-shaped seat frame 23.

The free end 25 of the U-shaped seat frame 23 has an upwardly curved arm 27 secured thereto by a vertically extending pivot 28 so that the arm 27 can swing laterally thereabout. A tubular cam 26 is secured to the terminal end of the arm 27 with its axis generally perpendicular to the U-shaped frame 23.

The tubular cams 26 are identical and are each provided with a relatively wide spiral slot 29 extending from the upper to the lower edge thereof, as can be best seen in Figures 2 and 3. The spiral slot 29 is of sufiicient width to permit the tubular upright members 20, 21 to pass therethrough when the slot 29 is aligned therewith, as viewed in Figure 3.

In the use and operation of the invention, the seat frame 23 is tilted to the position illustrated in Figure 3, and the slots 29 in the tubular cams 26 are engaged over the upright members 20, 21 of the back 19. The frame 23 is then lowered so that the tubular cams 26 bind against the uprights 20, 21 to support the seat 22 in position with respect to the chair 10.

The frame 23 can be vertically adjusted with respect to the back 19 by slightly raising the forward end of the frame 23 to release the grip of the cams 26 with the upright members 20, 21. In those cases where the upright members 20, 21 are not parallel, the arm 27 will swing on the pivot 28 as the frame 23 is raised or lowered thus preventing the cams 26 from binding during the adjustment of the frame 23.

The pivotal action of the arm 27 also permits the lateral adjustment of the tubular cams 26 with respect to each other to fit chairs having tubular uprights 20, 21 of varying widths.

While the seat 22 has been shown attached to a chair 10 to provide the only seat therefor, it should be understood that the vertical adjustable seat 22 can be attached to chairs having a fixed seat forming a part of their structure.

Having thus described the preferred embodiment of the invention, it should be understood that numerous structural modifications and adaptations may be resorted to without departing from the scope of the appended claim.

What is claimed is:

A demountable chair seat for use on a chair having a tubular framework including a back having a pair of rigid spaced parallel generally upright tubular members connected at their upper ends by an integrally formed bight portion, said demountable chair seat comprising a U-shaped seat frame having a pair of spaced apart free ends, a seat supported on said U-shaped frame, and a tubular cam lock fixedly secured on each of said free ends of said U-shaped frame for engagement about a respective one of said upright members, each of said cam locks having a spiral slot extending from the upper to the lower ends thereof, each of said slots opening in the same 3 direction whereby said cams can be laterally displaced from or toward said upright members upon tilting the seat frame upwardly for removal or mounting of the seat frame upon said upright members.

References Cited in the file of this patent UNITED STATES PATENTS 557,063 Faneuf Mar. 24, 1896 41 Chamberland July 7, 1903 Carter Sept. 24, 1912 Lister July 3, 1923 Harf -1 Jan. 31, 1956 Valente Feb. 5, 1957 FOREIGN PATENTS Germany June 1, 1913 Great Britain Dec. 8, 1947 

